Causal
strong strength
Narrative Connection
How these two moments in the story relate
From
Doctor Romana realize wrong planet
S18E9
·
Full Circle Part 1
To
Doctor and K9 investigate alien fog
S18E9
·
Full Circle Part 1
Why These Connect
The narrative assertion
"The Doctor and Romana's confirmation that they are not on familiar Gallifrey terrain directly prompts their inquiry about the fog at the lake. This introduces the local crisis of Mistfall and connects the TARDIS displacement to the planet's unfolding catastrophe."
About Causal Connections
A directly causes B. The first event sets forces in motion that produce the second. These are the load-bearing connections of plot--remove one and the story structure collapses.